From 643b64025650d0ac5d57bd522d2eb0996a278081 Mon Sep 17 00:00:00 2001 From: Ping Li Date: Tue, 20 Oct 2026 19:48:07 +0800 Subject: [PATCH] arm_mpam: Release the mon_sel lock on mpam_save_mbwu_state() errors mpam_save_mbwu_state() takes the mon_sel lock at the top of each loop iteration, but the four error paths that return after failed MPAMF_MON_SEL register accesses do so without releasing it. Take the lock with the conditional mon_sel_lock guard class instead, so all exit paths release it. Fixes: a3a94c13c442 ("arm_mpam: propagate MSC access errors for state saving function") Signed-off-by: Ping Li Reviewed-by: Ben Horgan Reviewed-by: Andre Przywara Signed-off-by: Catalin Marinas --- drivers/resctrl/mpam_devices.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/drivers/resctrl/mpam_devices.c b/drivers/resctrl/mpam_devices.c index 48adc49b833c..c067b6d57d71 100644 --- a/drivers/resctrl/mpam_devices.c +++ b/drivers/resctrl/mpam_devices.c @@ -2037,8 +2037,10 @@ static int mpam_save_mbwu_state(void *arg) struct mpam_class *class = ris->vmsc->comp->class; for (i = 0; i < ris->props.num_mbwu_mon; i++) { - if (WARN_ON_ONCE(!mpam_mon_sel_lock(msc))) - return -EIO; + ACQUIRE(mon_sel_lock, guard)(msc); + ret = ACQUIRE_ERR(mon_sel_lock, &guard); + if (ret) + return ret; mbwu_state = &ris->mbwu_state[i]; cfg = &mbwu_state->cfg; @@ -2061,10 +2063,8 @@ static int mpam_save_mbwu_state(void *arg) cfg->partid = FIELD_GET(MSMON_CFG_x_FLT_PARTID, cur_flt); mbwu_state->enabled = FIELD_GET(MSMON_CFG_x_CTL_EN, cur_ctl); - if (!mbwu_state->enabled) { - mpam_mon_sel_unlock(msc); + if (!mbwu_state->enabled) continue; - } val = 0; mbwu_arg = (struct mon_read) { @@ -2088,8 +2088,6 @@ static int mpam_save_mbwu_state(void *arg) ret = mpam_write_monsel_reg(msc, CFG_MBWU_CTL, 0); if (ret) return ret; - - mpam_mon_sel_unlock(msc); } return 0;